This invention relates to the ease of coupling a trailer to a towing vehicle and is more particularly concerned with improvements to a coupling ball joint between a trailer and towing vehicle, whereby the coupling is well suited for highway use. This invention provides an easy method of coupling between a trailer and a towing vehicle with a coupling ball joint without the need of accurate positioning alignment of the trailer and towing vehicle to effect a coupling hitch connection.
Prior art proposes a variety of methods to draw a trailer to a towing vehicle by means of a winch driven cable hitch system. Representative of such winch assisted hitches are the following; U.S. Pat. Nos.; Clark, Pat. No.5,048,854, Issued Sep. 17, 1991; Belcher, Pat. No. 4,807,899, Issued Mar. 4, 1988, and DeVorak, Pat. No. 4,466,632, Issued Aug. 21, 1984. These devises provide for an operator to position the location of a towing vehicle where upon a hitch connection or coupling ball attached to the towing vehicle is within close proximity of a hitch connection or trailer hitch coupler attached to the trailer such that the length of cable on a winch drum can be drawn off the winch drum and connected to the trailer hitch coupler without realignment of either the trailer or the towing vehicle. After the cable connection is made on the trailer hitch coupler, the winch is driven to draw the trailer to the towing vehicle by means of the winch system and thus effect a connection between the trailer and towing vehicle.
This invention is an improvement on the above described prior art by simplifying and eliminating the tongue and sleeve parts and associated locking pins, thereby improving the strength and reliability of the hitch system and reducing the costs of manufacture of said hitch systems.
Additionally, this invention eliminates the problems associated with engagement of a tongue and sleeve arrangement that is characteristic of the above mentioned prior art. One of the problems is the high load stresses on the cable from the trailer weight as the tongue is being drawn into the sleeve at odd angles of engagement, thereby increasing the risk of cable breakage and safety to the operator. The Clark '854 Patent best reduces this problem by allowing the sleeve assembly attached to the towing vehicle to pivot and self align as the trailer is being drawn to the towing vehicle by means of the winch system.
Another improvement to prior art of a coupling ball joint is that the alignment of the trailer hitch coupler to the coupling ball must be precise in order to effect proper engagement to allow the operator to secure the connection with a locking lever. If the alignment is not precise the trailer hitch coupler will bind over the coupling ball on the locking lever mechanism of the trailer hitch coupler and further manual assistance by the operator is required to get proper engagement to actuate the locking lever for securing the connection. Sometimes the operator will have to move the tow vehicle slightly forward to effect proper engagement or nesting of the trailer hitch coupler over the coupling ball. This invention will provide an assist for the nesting of the trailer hitch coupler over the coupling ball by means of the cable and winch drawing the trailer hitch to the tow vehicle.